2012 Vol. 2, No. 4

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2012, 02(4): 后插1-后插2,封3.
Abstract(63) PDF(0)
Abstract:
Second-order calibration applied to quantification of two active components of Schisandra chinensis in complex matrix
Xiao-Hua Zhang, Hai-Long Wu, Jian-Yao Wang, Yao Chen, Yong-Jie Yu, Chong-Chong Nie, Chao Kang, De-Zhu Tu, Ru-Qin Yu
2012, 02(4): 241-248.
Abstract(67) PDF(0)
Abstract:
The effectiveness of traditional Chinese medicine (TCM) against various diseases urges more low cost,speed and sensitive analytical methods for investigating the phamacology of TCM and providing a theoretical basis for clinical use.The potential of second-order calibration method was validated for the quantification of two effective ingredients of Schisandra chinensis in human plasma using spectrofluorimetry.The results obtained in the present study demonstrate the advantages of this strategy for multi-target determination in complex matrices.Although the spectra of the analytes are similar and a large number of interferences also exist,second-order calibration method could predict the accurate concentrations together with reasonable resolution of spectral profiles for analytes of interest owing to its ‘second-order advantage'.Moreover,the method presented in this work allows one to simply experimental procedure as well as reduces the use of harmful chemical solvents.
Quantification of sibutramine and its two metabolites in human plasma by LC-ESI-MS/MS and its application in a bioequivalence study
Venkata Suresh Ponnuru, B.R.Challa, RamaRao Nadendla
2012, 02(4): 249-257. doi: 10.1016/j.jpha.2012.02.010
Abstract:
Obesity can be considered as a chronic illness of epidemic proportion and its incidents have increased exponentially in recent years.The use of anti-obesity drugs such as sibutramine is somewhat helpful.There is a need to quantify such drugs in biological samples,which is generally quite difficult.In this report,we developed and validated a simple,sensitive and specific liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the quantification of sibutramine (SB) and its two metabolites N-des methyl sibutramine (DSB) and N-di desmethyl sibutramine (DDSB) in human plasma.Zorbax SBC18 (4.6 mm × 75 mm,3.5 μm,80 (A)) analytical column and 5 mM ammonium formate:acetonitrile (10∶90,v/v) mobile phase were used for chromatographic separation of SB,DSB and DDSB.Multiple reaction monitoring (MRM) in the positive mode was used to detect SB,DSB and DDSB at m/z 280.3/124.9,266.3/125.3 and 252.2/124.9,respectively.Liquid liquid extraction was used for the extraction of analytes and internal standard from human plasma.This method was validated over a linear concentration range of 10.0-10,000.0 pg/mL for SB,DSB and DDSB with correlation coefficients (r) of ≥0.9997.The drug and the two metabolites were stable in plasma samples.The validated method was successfully applied in a bioequivalence and pharmacokinetic study with human volunteers under fasting condition.
Preparative isolation and purification of 12,13-dihydroxyeuparin from Radix Eupatorii Chinensis by high-speed counter-current chromatography
Mei Yang, Xin-Jun Xu, Chun-Yan Xie, Jie-Yun Huang, Zhi-Sheng Xie, De-Po Yang
2012, 02(4): 258-263. doi: 10.1016/j.jpha.2012.03.004
Abstract:
An efficient method for the isolation and purification of 12,13-dihydroxyeuparin from Radix Eupatorii Chinensis by high speed counter-current chromatography (HSCCC) was established in this paper.The ether extracts of Radix Eupatorii Chinensis were purified by HSCCC with a solvent system of hexyl hydride ethyl acetate-methanol-water (1∶2∶1∶2,v/v/v/v).The upper phase was used as the stationary phase and the lower phase as the mobile phase.About 8.4 mg of 12,13-dihydroxyeuparin was obtained from 200 mg of ether extracts from Radix Eupatorii Chinensis in one-step HSCCC separation,with the purity of 96.71%,as determined by HPLC.After methanolwater recrystallization,the purity of 12,13-dihydroxyeuparin reached 99.83%.Such a simple and effective method was fairly useful to prepare pure compound as reference substances for related study on Radix Eupatorii Chinensis.
LC-UV and LC-MS evaluation of stress degradation behavior of desvenlafaxine
Shubhangi M.Pawar, Laxman D.Khatal, Satish Y.Gabhe, Sunil R.Dhaneshwar
2012, 02(4): 264-271.
Abstract(96) PDF(2)
Abstract:
The objective of current study was to develop a validated specific stability indicating reversed-phase liquid chromatographic method for the quantitative determination of desvenlafaxine in bulk sample and pharmaceutical dosage form in the presence of degradation products.Forced degradation studies were performed on bulk sample of desvenlafaxine as per ICH prescribed stress conditions using acid,base,oxidative and photolytic degradation to show the stability indicating power of the method.Significant degradation was observed under acidic stress condition and the degradation product formed was identified by LC-MS and a degradation pathway for drug has been proposed.Successful separation of drug from degradation products formed under stress conditions was achieved on a SymmetryShield column C18 (5 μm,250 mm × 4.6 mm,i.d.) using the mobile phase consisting of a mixture of 0.2% (v/v) triethylamine in ammonium acetate (0.05 M; pH 6.5) and methanol using isocratic gradient.
A validated stability-indicating LC method for the separation of enantiomer and potential impurities of Linezolid using polar organic mode
T.Satyanarayana Raju, O.Vishweshwari Kutty, V.Ganesh, P.Yadagiri Swamy
2012, 02(4): 272-278.
Abstract(79) PDF(0)
Abstract:
Although a number of methods are available for evaluating Linezolid and its possible impurities,a common method for separation if its potential impurities,degradants and enantiomer in a single method with good efficiency remain unavailable.With the objective of developing an advanced method with shorter runtimes,a simple,precise,accurate stability-indicating LC method was developed for the determination of purity of Linezolid drug substance and drug products in bulk samples and pharmaceutical dosage forms in the presence of its impurities and degradation products.This method is capable of separating all the related substances of Linezolid along with the chiral impurity.This method can also be used for the estimation of assay of Linezolid in drug substance as well as in drug product.The method was developed using Chiralpak IA (250 mm × 4.6 mm,5 μm) column.A mixture of acetonitrile,ethanol,n-butyl amine and trifluoro acetic acid in 96:4:0.10:0.16 (v/v/v/v) ratio was used as a mobile phase.The eluted compounds were monitored at 254 nm.Linezolid was subjected to the stress conditions of oxidative,acid,base,hydrolytic,thermal and photolytic degradation.The degradation products were well resolved from main peak and its impurities,proving the stability-indicating power of the method.The developed method was validated as per International Conference on Harmonization (ICH) guidelines with respect to specificity,limit of detection,limit of quantification,precision,linearity,accuracy,robustness and system suitability.
Two spectrophotometric methods for simultaneous determination of some antihyperlipidemic drugs
Nada S.Abdelwahab, Badr A.El-Zeiny, Salwa I.Tohamy
2012, 02(4): 279-284. doi: 10.1016/j.jpha.2012.02.002
Abstract:
Two simple,accurate,precise and economic spectrophotometric methods have been developed for simultaneous determination of Atorvastatin calcium (ATR) and Ezetimibe (EZ) in their bulk powder and pharmaceutical dosage form.Method (Ⅰ) is based on dual wavelength analysis while method (Ⅱ) is the mean centering of ratio spectra spectrophotometric (MCR) method.In method (Ⅰ),two wavelengths were selected for each drug in such a way that the difference in absorbance was zero for the second drug.At wavelengths 226.6 and 244 nm EZ had equal absorbance values; therefore,these two wavelengths have been used to determine ATR; on a similar basis 228.6 and 262.8 nm were selected to determine EZ in their binary mixtures.In method Ⅱ,the absorption spectra of both ATR and EZ with different concentrations were recorded over the range 200-350,divided by the spectrum of suitable divisor of both ATR and EZ and then the obtained ratio spectra were mean centered.The concentrations of active components were then determined from the calibration graphs obtained by measuring the amplitudes at 215-260 nm (peak to peak) for both ATR and EZ.Accuracy and precision of the developed methods have been tested; in addition recovery studies have been carried out in order to confirm their accuracy.On the other hand,selectivities of the methods were tested by application for determination of different synthetic mixtures containing different ratios of the studied drugs.The developed methods have been successfully used for determination of ATR and EZ in their combined dosage form and statistical comparison of the developed methods with the reported spectrophotometric one using F and Student's t-tests showed no significant difference regarding both accuracy and precision.
Synchronized separation of atorvastatin-an antihyperlipidemic drug with antihypertensive, antidiabetic,antithrombotic drugs by RP-LC for determination in combined formulations
M.V.N.Kumar Talluri, Anitha Kalyankar, Srinivas Ragampeta
2012, 02(4): 285-292. doi: 10.1016/j.jpha.2012.02.006
Abstract:
A new rapid and sensitive high performance liquid chromatography (HPLC) method has been developed for the simultaneous determination of atorvastatin-an antihyperlipidemic drug along with most commonly prescribed drugs (antihyperlipidemic,antihypertensive,antidiabetic,antithrombotic) in bulk and marketed combined formulations.The chromatographic separation was carried out by gradient elution mode with acetonitrile as organic modifier and 0.1% triethylamine acetate (TEAA) buffer pH 5 at a flow rate of 1 mL/min and a diode array detector at wavelength 230 nm was employed for detection of the analytcs.Calibration curves were linear in the range of 5 -150 μg/mL for all the drugs with correlation coefficients of determination (r2 values) ≥ 0.999.Limits of detection (LODs) and Limits of quantification (LOQs) ranged from 0.1 to 0.27 μg/mL and 0.3 to 0.89 μg/mL respectively.Intra-day and inter-day precision was studied at three concentration levels (20,60 and 100 μg/mL).The intra-day and inter-day RSD for all compounds was less than 2.0%.The accuracy for all compounds was found to be between 98% and 102%.Thus,the performance of the method described allows its use in quantification of atorvastatin along with 9 most commonly prescribed drugs available in market as atorvastatin combined dosage forms.
Cytotoxicity and cellular imaging of quantum dots protected by polyelectrolyte
Hai-Yan Hu, Xing-Ru Dou, Zong-Lin Jiang, Jian-Hua Tang, Lian Xie, Hong-Ping Xie
2012, 02(4): 293-297. doi: 10.1016/j.jpha.2012.02.003
Abstract:
The nanocomposites of poly-diallyldimethylammonium chloride (PDADMAC) and CdTe quantum dots (QDs) (i.e.QDs-PDADMAC nanocomposites) have been prepared based on electrostatic interaction and their fluorescence stability in aqueous solution has been investigated. MTT method (3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide method) was used to study their cytotoxicity and A549 lung cancer cell as a model cell was also used to evaluate their cellular imaging.It was shown that the fluorescence stability of QDs-PDADMAC nanocomposites was much better than that of bare QDs both in aqueous solution and cell.Meanwhile,QDs-PDADMAC nanocomposites display very low cytotoxicity in the low concentrations and better staining ability compared with QDs.QDs-PDADMAC nanocomposites will have great advantage on the cell analysis detection and imaging.
Stability-indicating liquid chromatographic method for the determination of Letrozole in pharmaceutical formulations
M.Mathrusri Annapurna, Chitaranjan Mohapatro, A.Narendra
2012, 02(4): 298-305. doi: 10.1016/j.jpha.2012.01.010
Abstract:
A stability-indicating high-performance liquid chromatographic method was developed and validated for the determination of Letrozole in tablet dosage forms.Reversed-phase chromatography was performed on Shimadzu Model LC-Class-Vp with Lichrocart/Lichrosphere 100 C-18 (250 mm × 4.6 mm,5 μm particle size) column with methanol:tetra butyl ammonium hydrogen sulfate (80:20V/V) as mobile phase at a flow rate of 1 mL/min with UV detection at 240 nm.Linearity was observed in the concentration range of 0.5 150 μg/mL (R2=0.9998) with regression equation y=102582x+43185.The limit of quantitation (LOQ) and limit of detection (LOD) were found to be 0.043 and 0.012 μg/mL respectively.The forced degradation studies were performed by using HCI,NaOH,H2O2,thermal and UV radiation.Letrozole is more sensitive towards alkaline conditions and very much resistant towards acidic,oxidative and photolytic degradations.The method was validated as per ICH guidelines.The RSD for intra-day (0.78-0.97) and inter-day (0.86-0.96) precision were found to be lesser than 1%.The percentage recovery was in good agreement with the labeled amount in the pharmaceutical formulations and the method is simple,specific,precise and accurate for the determination of Letrozole in pharmaceutical formulations.
Azeotropic mixture used for development and validation of Lornoxicam in bulk and its tablet dosage form by spectrophotometric method
Prajesh Prajapati, Vipul Vaghela, Deepak Rawtani, Harshad Patel, Jasmin Kubavat, Dharmendra Baraiya
2012, 02(4): 306-309. doi: 10.1016/j.jpha.2012.02.004
Abstract:
A novel,safe,economic and sensitive method of spectrophotometric estimation has been developed using Azeoptropic mixture (water∶methanol:60∶40,v/v) for the quantitative determination of Lornoxicam,a practically water-insoluble drug.Hence,Lornoxicam stock solution was prepared in Azeoptropic mixture.Lornoxicam showed maximum absorbance at 383 nm.Beer's law was obeyed in the concentration range 4-24 μg/mL with regression coefficient of 0.999.The method was validated in terms of linearity (R2=0.999),precision (CV for intra-day and inter-day was 0.28 0.68 and 0.12-0.92,respectively),accuracy (98.03-100.59% w/w) and specificity.This method is simple,precise,accurate,sensitive and reproducible and can be used for the routine quality control testing of the marketed formulations.
Rapid analysis of piperazine ferulate tablets by optic-fiber sensing technology and the similarity of ultraviolet spectra
Li Li, Chun-Ling Zhang, Lu Jin, Cui-Juan Feng
2012, 02(4): 310-313.
Abstract(59) PDF(0)
Abstract:
A rapid analysis method of piperazine ferulate tablets by optic-fiber sensing technology with UV-vis absorption spectrum was established.Qualitative and quantitative data were obtained and compared by maximum and minimum wavelength,absorbance and contrast spectra.Similarity method was used to identify authenticity of drugs.The difference of contents measured by this method and UV determination method in China Pharmacopoeia showed no statistical significance (P>0.05),while the similarity can be used as a parameter to identify the authenticity of drugs.
Determination of genotoxic alkyl methane sulfonates and alkyl paratoluene sulfonates in lamivudine using hyphenated techniques
N.V.V.S.S.Raman, A.V.S.S.Prasad, K.Ratnakar Reddy, K.Ramakrishna
2012, 02(4): 314-318. doi: 10.1016/j.jpha.2012.03.003
Abstract:
Two highly sensitive methods for the determination of genotoxic alkyl methane sulfonates (AMSs) and alkyl paratoluene sulfonates (APTSs) in lamivudine using hyphenated techniques have been presented.AMSs were determined by GC-MS method using GSBPINOWAX (30 m × 0.25 mm × 0.25 μm) column.Temperature program was set by maintaining at 100 ℃ initially for 3 min,then rised to 220 ℃ at the rate of 15 ℃/min and maintained at 220 ℃ for 16 min.N,N-dimethyl formamide was used as diluent.APTSs were determined by LC-MS using Zorbax,Rx C8,250 mm × 4.6 mm,5 μm column as stationary phase.0.01 M ammonium acetate is used as buffer.The mixture of buffer and methanol in 75∶25 (v/v) ratio was used as mobile phase A and mixture of buffer and methanol in 5∶95 (v/v) ratio was used as mobile phase B.The gradient program (T/%B) was set as 0/28,16/50,17/100,23/100,27/28 and 40/28.Both the methods were validated as per International Conference on Harmonization guidelines.Limit of quantitation was found 1.5 μg/mL for AMSs and was in the range of 1.0-1.5 μg/mL for APTSs.